Abstract 2474: Dynamic Change in LV Twist Mechanics in a Canine Model of Pacing-Induced Heart Failure

• DOI: 10.1161/circ.116.suppl_16.ii_544-d
• Publication Date: 2021-07-03T01:30:53Z
• Authors: Jianwen Wang; Sherif F Nagueh; Nilesh Mathuria; April L Gilbert; Daryl G Schulz; Dorin Panescu; Hue-Teh Shih; Dirar S Khoury
• Keywords: Preload; Contractility

Background : LV twist may reflect contractility under different conditions. This study investigated dynamics and its determinants in a canine model of congestive heart failure (CHF). Methods Pacemakers percutaneous leads were implanted 8 adult hound dogs (mean weight, 38 kg), continuous chronic RV pacing was applied at 230–250 bpm until CHF induction. Subsequently, turned off to allow the recover. Echocardiography catheterization performed simultaneously baseline, during while temporarily switched off, recovery from after stopped. induction by repeated 4 dogs. Apical basal rotations measured using 2D speckle tracking, calculated as difference between apical rotations. Untwisting rate peak diastolic time derivative twist. Results developed 2–4 wks with end-diastolic volume (LVEDV), end-systolic (LVESV), pressure (LVEDP), constant relaxation isovolumic period (tau) all increasing significantly compared baseline (Table ), recovering levels untwisting decreased improved although change not significant. In pooled data, related LVEDV (r=-0.60, P<0.001), LVESV (r=-0.59, P=0.001), LVEF (r=0.81, LVEDP (r=0.41, P=0.03) +dp/dt (r=0.71, but (r=0.06, P=0.77). multiple analysis, only independent predictor (P < 0.001). Conclusions can presence pacing-induced recovery. appears be determinant CHF.